Surface condenser



March 15, 1938. r ACE 2,111,240

I SURFACE'CONDENSER Filed Feb. 19, 1936 5 sheets sheet 1 Jon F. GRACE.

INVENTOR By W? ATT RNEY March 15, 1938. J F RA E SURFACE CONDENSER FiledFeb. 19, 1936 5 Sheets-Sheet 2 JUHIN E ER'mzE.

IN VEN TOR ATTRNEY Rdarch l5, 1935i J p SURFACE CONDENSER Filed Feb. 19,1936 5 Sheets-Sheet 5 JOHN F.GRAC-EQ.

LNVENTOR A ORNEY March 15, 1938. J. F CE SURFACE CONDENSER 5Sheets-Sheet 4 Filed Feb. 19, 1936 JOHN F. GRaoEa INVENTOR BY ATTORNEYMarch 15, 1938. F RA E w 2,111,240

SURFACE CONDENSER JoHN E GRacE.

INVENTOR Patented Mar. 15, 1938 UNITED STATES PATENT OFFICE SURFACECONDENSER Application February 19, 1936, Serial No. 64,787

29 Claims.

This invention relates to surface condensers for condensing steam andthe primary object of the invention is to provide a surface condenser inwhich the shell or housing is built up of sheet metal sections, weldedor otherwise suitably connected at the joints, and in which the shell isconstructed to withstand the stresses imposed upon the shells orhousings of large steam condensers of the surface type, with a minimumamount of cross bracing, and with a high degree of simplicity in itsconstruction, thereby provid ing a sheet metal shell condenser, which isstrong, durable and one which may be manufactured at a relatively lowercost with respect to the cost of the shells or housings of approved typeof surface condensers of comparative surface area.

In surface condensers of large surface area and condensing capacity asemployed in present-day modern power plants, the condenser shells orhousings are subjected to heavy stresses, due principally to theabsolute pressure of the atmosphere exterior of the condenser and partlyto the temperature variances to which they are subjected andthe loadthey must carry because of the weight of the parts, and the method ofattaching to the turbine, etc. Heretofore, it has been the generalpractice to construct the shells or housings of such condensers,particularly those of large area and capacity, of heavy cast metal ofsufficient weight and strength to withstand the stresses; however, thepresent-day tendency is towardssheet metal shells, because of cheapnessof such shells, and lighter Weight, etc. With the advent of such sheetmetal shell condensers, arose the problem of strength to Withstand thestresses of operating conditions Without resorting to excess bracing andinterference with the condensing space and the flow of steam into andthrough the condenser.

The present invention comprises a condenser shell in which the shellitself embodies in its construction novel characteristics or featuresthat enable it to withstand the stresses'to which it is subjected duringoperation and in which such cross bracing as is employed serves the dualfunction of strengthening and bracing the shell, and forming supportsfor the segmental support plates employed for supporting the tubes usedfor the circulation of the cooling medium through the condenser.

A further object of the present invention is'to provide in a steamcondenser as specified a novel construction and arrangement of supportplates for supporting the cooling medium circulating tubes, withoutimposing or permitting any abnormal or excessive stresses on any part ofthe condenser shell, and which support plates are arranged to permitunimpeded flow of steam to be condensed longitudinally to all parts ofthe condenser as well as to permit penetration of the steam to all partsof the condensing surface of the condenser, thereby obtaining maximumcondensing of steam with a, minimum amount of tube or condensingsurface.

Another object of the present invention is to provide in a surfacecondenser for steam as specifled a novel arrangement and construction ofshell, braces, and supporting plates, which will provide maximumsupporting strength and will not interrupt or abruptly divert the steamflow through the condenser, with the resultant creation of air pocketsor dead spaces.

With these and other objects in View, as may appear from theaccompanying specification, the invention consists of various featuresof construction and combination of parts which will be first describedin connection with the accompanying drawings, showing a condenser of thepreferred form embodying the invention, and the features forming theinvention will be specifically pointed out in the claims.

In the drawings:

Figure l is a side elevation of the improved surface condenser.

Figure 2 is an end elevation of the condenser.

Figure 3 is a perspective view of the condenser, having the water boxand one-half of one of the tube sheets removed to show the interiorarrangement of the support plates and braces in the shell.

Figure 4 is a cross-section through the condenser taken on the line 4-4of Figure 1.

Figure 5 is a longitudinal section through the condenser taken on theline 5-5 of Figure 4 but having the water boxes removed.

Figure 6 is a detail perspective of a part of the condenser structure.

Figures '7, 8 and 9 are detail views in elevation of the differentsections which go to make up the support plates of the condenser.

Figure 10 is a perspective view of a modified form of the condenser,having awater box and tube sheet removed and parts broken away toillustrate the interior construction of the condenser.

Referring more particularly to the drawings, the improved condensercomprises a shell generically indicated by the numeral l. The shell I-has the usual tube sheets 2 and 3 attached at the ends thereof to whichthe ends of the tubes (not shown) used for circulating the cooling waterfrom one of the water boxes 4 or 5 through the condensing space to theother water box are attached in any approved manner.

The water circulating tubes are of the usual approved type employed insurface condensers and they are left out of the drawings so as not toobscure unnecessarily the details of the interior construction of thecondenser.

In the drawings the condenser is shown as what is commercially known asa single pass condenser, that is, the cooling water enters the water box4 through the inlets 6, passes through the condensing space into thewater box 5 and passes out of the water box through the outlets 1. Whilethe condenser is illustrated as a single pass condenser it is to beunderstood that the features of the condenser forming the presentinvention may be embodied with a two pass condenser or a condenser ofany multiple. number of passes for the circulating of cooling waterwithout departing from the spiritv of the present invention.

The shell I of the condenser is formed of sections of sheet metal whichare preferably welded at the joints but may be connected in any suitablemanner without departing from the spirit of the invention, and it is tobe understood that the shell may be made of any number of connectedsections, depending upon the size of the shell.

The lower portion 8 of the shell I is formed of curved sections whichpresent concave surfaces to the interior of the condenser and in theconstruction shown in the drawings, the middle portion 9 of the upperpart In of the condenser is also shown as formed of sections II and I2of sheet metal which are curved so as to present convex surfaces to theouter side of the condenser and concave surfaces inwardly to theinterior of the condenser. The condenser illustrated is shown asprovided with two inlets I4 and I5 for exhaust steam. However, theinvention is equally applicable to condensers having a single exhauststeam inlet or any desired and practical number of exhaust steam.inlets. The sides I5 of the exhaust steam inlets which also form part ofthe condenser shell, are curved to present concave surfaces to theexterior of the condenser shell conversely to the curvature of thesections 8 and I These sides I6 are curved in the manner illustrated soas to guide properly the incoming steam into the condenser shell forproper delivery of the steam into the condensing space of the condenser.As clearly shown in Figure 4 of the drawings, the condensing space,identified by the uppermost portions of the support plates and thediagrammatic outline of the tube bank in Figure 3 of the drawings,commences substantially in a line with or slightly above the plane inwhich the sides Iii begin to curve outwardly so that the incoming steamengaging along the convex inner surfaces of the sides IE will passtangentially off these convex surfaces into the tube bank or condensingspace next the sides of the condenser. Part of such steam will enter thetube banks near their top while the remaining portion of it will passdownwardly through the steam lanes indicated at IT and enter thecondensing surface or tube bank at points below the uppermost partthereof. It is to be understood, of course, that steam enters thecondenser shell through the entire opening or space in the exhaustinlets l4 and I5 and it is only the steam which enters at the endportions of such inlets that is referred to above in connection with theinterior convex surface of the sides I6.

The condenser shell embodies two straight sections 20 and 2I which arein the form of flat I beams, the lower ends of which are bolted, weldedor otherwise suitably attached to the flanges 22 formed on the upperedges of the sections forming the lower portion 8 of the condenser whilethe upper edges of these straight absorbing bracing flat sections areattached in any suitable manner, preferably by bolting, to the flanges23 which are formed upon the lower edges of the sections forming theportion 9 and of the sides I6 of the. exhaust inlets I d and I5. Theconcave curvature of the sides I6 together with the straight verticalbeams or sections 2i and the convexly curved sections forming theportion 8 of the condenser all cooperate and combine to strengthen theshell I of the condenser in such manner as to absorb effectively thestresses to which the condenser shell is subjected during operation. Thestraight fiat sections 20, it will be noted are placed or extend alongthe sides of the shell at the center of the condenser and providerelatively long straight stress-absorbing sections which are supporteddirectly upon the supporting feet 25 of the condenser therebytransmitting through these flat straight sections 20 and 2|, thestresses of the condenser shell directly to the supporting feet 25 andthe foundation, indicated at 26, on which the condenser is supported. Ofcourse, it is to be understood that such straight flat sections 20 and2| are equally efficient in absorbing and distributing stresses of theconvexly curved sections I I and I2 as they are of the concavely curvedsections or sides I6, and also that they will be equally effective inabsorbing and transmitting stresses in condenser shells which do nothave the concave sections I6.

The exhaust inlets, the lower ends of the straight sections 20 and 2|and the top of the central or intermediate portion 9 of the condenserare all braced by suitable sheet metal braces 21 which are welded orotherwise suitably attached to the various parts of the condenser shellwhere required.

The shell I is braced transversely by a plurality of horizontal braces30 arranged in horizontal vertically spaced rows, and extending from oneside of the condenser to the. other, as clearly shown in Figures 3, 4,and 5 of the drawings.

The horizontal transversely extending braces 39 are composed oftransversely extending side rails 3! disposed in parallel relation andconnected preferably by cross braces 32 at spaced points.

The braces 30 in the uppermost row, that is, the braces nearest theexhaust steam inlets, have their ends suitably connected to the flatplates 33 of the brace structures 34. The fiat plates 33 are connectedor attached to the sides i6 by suit: able brackets 35 which are weldedor otherwise suitably attached to the shell of the condenser as clearlyshown in Figures 4 and 6 of the drawings.

The tubes, (not shown) through which the circulating water travels fromwater box to water box, are supported intermediate their ends, bysupport plates, as is usual in the construction of large surfacecondensers, however in the present invention, a particular novel type ofsupport plate is provided, which is segmental, each support plate unitbeing composed of a plurality of sections attached to and supported bythe cross braces 30 and the supporting or attaching brackets 35, so asto distribute throughout the length of the condenser shell, the weightand load of the condenser tubes for the purpose of distributing theweight in such manner as to impose as little stress as possible upon thecondenser shell at any concentrated point. Also the provision of thesegmental support plates provides sinuous paths longitudinally throughthe condenser and the condensing space which will permit the steam to becondensed to pass freely throughout the entire length of the condensingspace of the condenser.

Each support plate unit or assembly which supports all of the tubes atone location in the shell is composed primarily of two sections each extending transversely across approximately onehalf of the condensingsurface from a vertical space in the center toward one side.

Each of the sections, which are clearly shown in Figures 3, 4, '7, 8 and9 of the drawings, is

composed of a relatively small piece fill substantially kite shaped withits side edges converging as they extend downwardly and which conformsin shape to the space between the arms M of the V piece 42 of thesupport plate unit. The top or kite shaped piece 49 has its upper edgeat tached to the proper cross brace 30 in the uppermost row of the crossbraces and the V shaped pieces 42 have the upper ends of one of theirarms attached to the outside edge of the same proper cross brace 30 ofthe uppermost horizontal row of cross braces as indicated at 43 whilethe upper end of its other arm is attached to the proper attachingbracket 35 as shown at 44. The lower end of the substantially v-shapedpiece a2 is attached as shown at 45 to the proper cross brace 30 in thelowermost horizontal row of the cross braces and it may, if so desired,be attached to the proper cross brace 3% of the intermediate rows ofcross braces.

The third and final piece 46 of each of the support plate sections isrelatively large in comparison to the other two pieces of each sectionand it is cut away from its upper edge downwardly to provide a V-shapedspace into which the piece 42 will fit. The piece 46 has an arm 41 whichis attached to the same edge of the pro-per cross brace in the uppermostrow as the piece 40 i and this piece 46 is also attached at spacedpoints as indicated at 48 to the shell proper of the condenser and it issupported and rendered more rigid by attachment to the various crossbars 38. The pieces 46 and 40 are secured to the same edges of thetransverse braces 3%], but they are spaced apart to provide a space ofthe same size and shape as the piece 52 so that steam will pass aroundthe piece 42 and through the V-shaped space between the pieces 40 and46.

The pieces 46 of the support plates, which are clearly shown in Figure 7of the drawings are each cut away as indicated at 49 to provide spacefor the air cooling sections 50 of the condenser. In the drawings, thecondenser is shown as having an air-cooling section 50 on each sidethereof but it is to be understood that only one aircooling section maybe provided without departing from the spirit of the present inventionand that this air-cooling section may be located as shown in thedrawings or at any other convenient location with respect to thecondensing surface.

As clearly shown in Figure 5 of the drawings the relatively smallkite-shaped pieces 40 and the pieces 46 of each support plate sectionare placed in alignment with each other, while the substantiallyV-shaped piece 42 of each support plate section is positioned parallelto the pieces 49 and 4B but spaced therefrom so as to provide aplurality of sinuous paths opening longitudinally through the condenserto permit the free longitudinal flow of steam in either directionthroughout the entire length of the interior of the condensing space.This arrangement of the pieces of the support plates also distributesthe load 01' the support plates on the shell and prevents concentrationof the loads occasioned by the support plates and the tubes on the shellproper.

A novel type of partition structure is provided for partitioning off theair-cooler spaces 59 in the condenser. These partitions 5| are formed ofsheet metal and extend from end to end of the condensing space withinthe condenser shell. They have arch-like openings 52 cut therein atproper spaced intervals to permit entrance of air and uncondensed vaporinto the air-cooler sections 50, the partitions themselves preventingentrance of the air and uncondensed vapor into the air-cooler sectionsexcept through these openings 52. The plates or partitions 5| have theiredges which extend around the arch-like openings 52 bent or shaped toform drainage troughs 53 which serve to drain the condensate which fallsupon the partitions 5| downwardly into the bottom of the condenser shellalong the sides of the openings 52 preventing the condensate fromshowering across the openings 52.

The air-cooler sections 50 have tube supporting plates 54 therein whichare spaced staggeredly with respect to the support plate sections of themain condensing chamber of the condenser. The air and uncondensed vaporare taken off from the air cooler sections 50 through suitable air ofitakes 56.

Suitable dams or baffie plates 51 are located in the lowermost portionof the condenser shell and extend from end to end of the condenser for ashort distance upwardly into the condensing space for the purpose ofmaintaining the desired level of the condensate in the bottom of thecondenser outwardly of these baffle plates. The pieces 46 of the supportplate sections are provided with cut out portions 58 which permitlongitudinal flow of the condensate through the condenser shell.

The condensate flows from the condenser shell through a suitableoutlet-59 into the hot well 60. The hot well 60 may be either formed ofsheet metal or cast as desired and it is attached to the condenser shellproper in any suitable manner through the medium of the flangedattaching ring 6| which is welded or otherwise suitably connected to thecondenser shell. As clearly shown in Figure 4 of the drawings, theinterior or the condenser is provided with a longitudinally extendingcentral throughout its length and opens into the opening 59. This space62 is arranged to permit the direct passage of some of the exhaust steamentering the condenser, to the bottom of the condenser for the purposeof re-heating the condensate as it showers over the baflies 51 forpassage to the hot well and for heating the other condensate as itshowers downwardly through the condensing space between the baffles 51immediately prior to the passage of the condensate into the hot well. A

In the drawings a heater of any approved type is shown at 65. Howeverthis heater forms no part of the present invention.

In Figure of the drawings a slight modification of the improvedcondenser is shown. The only difference, however, between this modifiedform of the invention and the preferred form is in the construction ofthe support plates for the space 82 which extends cooling watercirculating tubes. In all other respects, the condenser is the same.That is, the condenser shell or housing in this preferred form embodiesthe straight I beam sections 20' and 2| which extend longitudinally ofthe shell I along its middle and are attached by suitable flanges to thecurved portions of the shell which form the upper and lower partsthereof.

The shell I has cross braces 30 therein which are of the same or similarconstruction to the cross braces 30 of the preferred form, it has theair cooler defining partitions 5 l the condensate damming baffles 51,etc.

The support plate structures are, however, different in this modifiedform and the means for supporting the cooling water circulating tubes(not shown) is a plurality of flat strips 10 of sheet metal which arearranged in angled relationship to each other and to the vertical andare disposed in aligning sets or tiers with the strips in one tierdisposed staggeredly with respect to the strips in the tier nextthereto. Kitelike sections II are provided which are attached to theproper braces 30' in the uppermost row of cross braces. Thesekite-shaped sections H are positioned to fit or fill spaces between theangled fiat strips 10 so that when looking at the condenser from the endsubstantially solid appearing support plates are provided or in otherwords supports are provided which cover the tube areas of the condensingspace. In other words support is provided, for all of the tubes (notshown) at relatively close transverse planes in the condensing spacewithout concentrating the load of the weight of the tubes and theirsupports at particular points on the shell I of the condenser, whichsupports distribute this weight or load over a large number of spacedpoints on the shell. The staggered arrangement of the supporting platesor strips also permits free unimpeded longitudinal travel of the steamthrough the condensing space of the condenser and insures or permitsthorough distribution of the steam in the condensing space together withthe resultant maximum condensing efficiency of the condenser which willcondense a maximum amount of steam with a minimum amount of tube surfaceand condensing space.

While in the foregoing description and in the drawings the surfacecondenser has been described and shown as being constructed of sheetmetal, it is to be understood that the principles of the invention maybe applied to condensers having cast iron shells, or shells and otherparts made of any suitable material in any suitable manner, withoutdeparting from the spirit of the invention.

What is claimed is:

1. In a surface condenser, a shell, an exhaust steam inlet for saidshell, the sides of said exhaust steam inlet being curved inwardly andoutwardly in a continuous curve from the mouth of the exhaust steaminlet to present convex surfaces to the interior of the shell.

2. In a surface condenser, a shell, an exhaust steam inlet for saidshell, a tube bank in said shell provided with steam lanes, the sides ofsaid exhaust steam inlet being curved inwardly and outwardly in acontinuous curve from the mouth of the exhaust steam inlet to presentconvex surfaces to the interior of the shell for directing incomingsteam into certain of said steam lanes from one part of the curvedsurfaces thereof and into other steam lanes from other portions of thecurved surfaces thereof.

3. In a surface condenser, a cylindrical shell embodying flat straightstress absorbing portions extending longitudinally of the shell from endto end thereof, a partition within said shell for defining anair-cooling space, said partition formed of sheet metal and providedwith spaced out out portions for forming entrance openings into theair-cooler section, and condensate drainage troughs on said partitionabout said openings.

4. In a surface condenser, a shell built up of a plurality of portionsof sheet metal, certain of said portions being transversely curved andother of said portions being transversely straight for absorbing anddistributing stresses, a partition within said shell for defining anair-cooling space, said partition formed of sheet metal and providedwith spaced out out portions for forming entrance openings intotheair-cooler section.

5. In a surface condenser, a shell, a partition within said shell fordefining an air-cooling space, said partition formed of sheet metalwelded to the shell flange and provided with spaced out out portions forforming entrance openings into the air-cooler section, the edge portionsof said metal sheet above said openings shaped to form condensatedrainage troughs.

6. In a surface condenser, a shell built up of sheet metal and includingupper and lower curved portions and fiat straight portions intermediatesaid upper and lower curved portions and attached thereto and extendingthroughout the length of the shell, support plates in said shell, saidsupport plates each composed of a plurality of pieces shaped to providea complete support plate section, certain pieces of each supportplatesection. being disposed staggeredly with respect to the otherpieces of the particular support plate section, a partition within theshell for defining an air-cooling space, said partition formed of sheetmetal and provided with spaced cut out portions for forming entranceopenings into the aircooler section.

'7. In a surface condenser, a shell built up of sheet metal andincluding upper and lower curved portions and fiat straight portionsintermediate said upper and lower curved portions and attached theretoand extending throughout the length of the shell, support plates in saidshell, said support plates each composed of a plurality of pieces shapedto provide a complete support plate section, certain pieces of eachsupport plate section being disposed staggeredly with respect to theother piece of the particular support plate section, a partition withinthe shell for defining an aircooling space, said partition formed ofsheet metal and provided with spaced out out portions for formingentrance openings into the air-cooler section, and tube supportingplates in said air-cooler section disposed staggeredly with respect tothe pieces of the support plate sections.

8. In a surface condenser, a shell built up of a plurality of portionsof sheet metal, certain of said portions being transversely curved andother of said portions being transversely straight for absorbing anddistributing stress, and transverse braces in said shell and havingtheir ends attached to said transversely straight portions, andsupporting feet for said shell engaging one edge of said straightportions.

9. In a surface condenser, a sheet metal shell built up of a pluralityof curved portions and a plurality of straight portions having edgewiseengagement with and connected to said curved portions, said condensershell having exhaust inlet openings, the side walls of said exhaustinlet openings being curved oppositely to the curvature of the remainingcurved portions of the shell and extending to the upper edges of saidstraight portions.

10. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of theshell, and flat straight stress absorbing and distributing portionsthroughoutthe length of the shell and extending in stress distributingcontinuation from the outside supports of the shell.

11. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions exmnding longitudinally of the shell,and fiat straight stress absorbing and distributing portions extendingthroughout the length of the shell and positioned between the upper andlower curved portions, said fiat portions having their fiat sidesparallel to a vertical plane bisecting the longitudinal center of theshell, and supporting feet for the condenser attached to the lower edgesof said straight fiat portions.

12. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of theshell, flat straight stress absorbing and distributing portionsextending throughout the length of the shell and positioned between theupper and lower curved portions, and transverse braces in said shell andhaving their ends attached to said straight portions for co-operatingtherewith in distributing stresses.

18. In a surface condenser having an air-cooling section, a shell builtup of sheet metal and including upper and lower curved portions and flatstraight portions intermediate said upper and lower curved portions andattached thereto and extending throughout the length of the shell,support plate units in said shell, said support plate units eachcomposed of a plurality of pieces shaped to provide a complete supportplate section for supporting all of the tubes in the condenser outsideof the air-cooling section, certain pieces of each support platesection. being disposed staggeredly with respect to the other pieces ofthe particular support plate section, cross braces having their endsattached to said flat straight portions, and certain of said supportplate units having one of their ends attached to a cross brace tofacilitate the distribution of stress in the condenser.

14. In a surface condenser, a shell formed of sheet metal, and tubesupporting means within said shell comprising flat metal pieces, certainof which are disposed in staggered relation to others, each of saidpieces connected to said shell at a point spaced from where anotherpiece is connected to the shell for distributing the tube and supportloads over'a wide area of the shell.

15. In a surface condenser, a shell, a partition Within the shell fordefining an air-cooling space, said partition formed of a single sheetof metal attached to said shell and extending from end to end of theinterior of the shell and provided with spaced out out portions forforming entrance openings into the air-cooler section.

16. In asurface condenser, a shell, a partition within the shell fordefining an air-cooling space, said partition formed of a single sheetof metal attached to said shell and extending from end to end of theinterior of the shell and provided with spaced out out portions forforming entrance openings into the air-cooler section, the edge portionsof said. sheet about said openings being shaped to form condensatedrainage troughs,

17. In a surface condenser, a shell built up of sheet metal andincluding upper and lower curved portions and fiat straight portionsintermediate said upper and lower curved portions and attached theretoand extending throughout the length of the shell, support plates in saidshell, said support plates each composed of a plurality of pieces shapedto provide a complete support plate section, certain pieces of eachsupport plate section being disposed staggeredly with respect to theother pieces of the particular support plate section, a partition withintheshell for defining air-cooling section, and tube supporting plates insaid air-cooler section disposed staggeredly with respect to the piecesof the support plate sections, the edge portions of said metal sheetabout said openings being shaped to form condensate drainage troughs,said shell having an exhaust steam inlet, the sides of said exhauststeam inlet being curved to present convex surfaces to the interior ofsaid shell.

18. In a surface condenser, a shell built up of sheet metal andincluding upper and lower curved portions and flat straight portionsintermediate said upper and lower curved portions and attached theretoand extending throughout the length of the shell, support plates in saidshell, said support plates each composed of a plurality of pieces shapedto provide a complete sup-port plate section, certain pieces of eachsupport plate sec tion being disposed staggeredly with respect to theother pieces of the particular support plate section, a partition withinthe shell for defining an air-cooling space, said partition formed ofsheet metal and provided with spaced out out portions for formingentrance openings into the air-cooler section, and tube supportingplates in said air-cooler section disposed staggeredly with respect tothe pieces of the support plate sections, the edge portions of saidmetal sheet about said openings being shaped to form condensate drainagetroughs, said shell having an exhaust steam inlet, the sides of saidexhaust steam inlet being curved to present convex surfaces to theinterior of said shell, and supporting feet for said shell engaging saidflat straight portions whereby stress will be transmitted from thestraight portions through said feet to a foundation on which thecondenser rests.

19. In a surface condenser, a sheet metal shell built up of a. pluralityof upper and lower curved portions extending longitudinally of theshell, and flat straight stress absorbing and distributing portionsthroughout the length of the shell and extending vertically from theline of support of the shell.

20. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of theshell, flat straight stress absorbing and distributing portionsthroughout the length of the shell and extending vertically from theline of support of the shell, and supporting feet for said shellengaging said flat straight portions whereby stress will be transmittedfrom the straight portions through said feet to a foundation on whichthe condenser rests. I

21. In a surface condenser, a sheet metal shell built up of a pluralityof upper andlower curved portions extending longitudinally of the shelland flat straight stress absorbing and distributing portions throughoutthe length of the shell, supporting feet for said shell engaging saidfiat straight portions, said flat straight portions extending instraight lines from said feet and the line of support of the feetwhereby stresses will be transmitted from the straight portions throughsaid feet to a foundation on which the condenser rests.

22. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of the shelland flat straight stress distributing and absorbing portions positionedbetween the upper and lower curved portions, transverse braces in saidshell and having their ends attached to said straight portions forco-operating therewith in distributing stresses, tube support plateunits in said shell, each of said support plate units being made up of aplurality of pieces attached to said transverse braces.

23. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of the shelland flat straight stress distributing and absorbing portions positionedbetween the upper and lower curved portions, transverse braces in saidshell and having their ends attached to said straight portions forco-operating therewith in distributing stresses, tube support plateunits in said shell, each of said support plate units being made up of aplurality of pieces attached to said transverse braces, certain of saidpieces of each support plate unit being arranged in longitudinallyspaced relation to other pieces in the same unit with said other of saidpieces being spaced in the same transverse plane through the shell.

24. In a; surface condenser, a welded sheet metal shell built up of aplurality of curved portions and a plurality of straight portions havingedgewise engagement with and connected to said curved portions, tubes insaid condenser shell and arranged to form central and side steam lanes,said condenser shell having exhaust steam inlet openings, the side wallsof said exhaust steam inlet openings being curved inwardly and outwardlyin a continuous curve from the mouth of the exhaust steam inlet topresent convex surfaces inwardly to the interior of the condenserwhereby entering steam will be tangentially projected off said innerconvex surface towards certain of said steam lanes.

25. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of theshell, fiat straight stress-absorbing and distributing portionsthroughout the length of the shell and extending vertically from theline of support of the shell, and cross-braces within the shell andattached to said fiat straight portions and extending across the shell.

26. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of theshell, flat straight stress-absorbing and distributing portionsthroughout the length of the shell and extending vertically from theline of support of the shell, cross-braces within the shell and attachedto said flat straight portions and extending across the shell, and tubesupporting support plate sections attached to said cross braces.

27. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of theshell, flat straight stress absorbing and distributing portionsthroughout the length of the shell and extending vertically from theline of support of the shell, said shell having an exhaust steam inlet,the sides of which inlet are curved inwardly and outwardly in acontinuous curve from the mouth of the exhaust steam inlet to presentconvex surfaces to the interior of the shell, and cross braces attachedto the curved sides of said exhaust steam inlet, and tube support platesections attached to said braces.

28. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of theshell, fiat straight stress absorbing and distributing portionsthroughout the length of the shell and extending vertically from theline of support of the shell, said shell having an exhaust steam inlet,the sides of which inlet are curved inwardly and outwardly in acontinuous curve from the mouth of the exhaust steam inlet to presentconvex surfaces to the interior of the shell, cross braces attached tothe curved sides of said exhaust steam inlet, tube support platesections attached to said braces, and cross braces attached to said flatstraight stress absorbing portions and extending across said shell, saidtube support plate sections being attached to said last-named crossbraces.

29. In a surface condenser, a sheet metal shell built up of a pluralityof upper and lower curved portions extending longitudinally of the shelland flat straight stress absorbing and distributing portions throughoutthe length of the shell positioned between the upper and lower curvedportions and extending vertically from the line of support of the shell,cross braces within the shell and attached to said fiat straightpositions and extending across the shell support plate units in saidshell each made up of a plurality of staggered pieces, certain of saidpieces having one of their ends attached to one of said cross braces forfacilitating distribution of stress in the condenser.

JOHN F. GRACE.

